Employee Benefit Plans and Collective Bargaining Agreements - Schedule of Plan Assets Allocation (Details) - Pension	Feb. 24, 2018	Feb. 25, 2017
Safeway Plan
Defined Benefit Plan Disclosure [Line Items]
Target allocations	100.00%
Actual allocations	100.00%	100.00%
Safeway Plan \| Equity
Defined Benefit Plan Disclosure [Line Items]
Target allocations	65.00%
Actual allocations	65.00%	63.10%
Safeway Plan \| Fixed income
Defined Benefit Plan Disclosure [Line Items]
Target allocations	35.00%
Actual allocations	35.50%	36.20%
Safeway Plan \| Cash and other
Defined Benefit Plan Disclosure [Line Items]
Target allocations	0.00%
Actual allocations	(0.50%)	0.70%
Shaw's Plan
Defined Benefit Plan Disclosure [Line Items]
Target allocations	100.00%
Actual allocations	100.00%	100.00%
Shaw's Plan \| Equity
Defined Benefit Plan Disclosure [Line Items]
Target allocations	65.00%
Actual allocations	65.40%	66.70%
Shaw's Plan \| Fixed income
Defined Benefit Plan Disclosure [Line Items]
Target allocations	35.00%
Actual allocations	32.20%	33.30%
Shaw's Plan \| Cash and other
Defined Benefit Plan Disclosure [Line Items]
Target allocations	0.00%
Actual allocations	2.40%	0.00%
United Plan
Defined Benefit Plan Disclosure [Line Items]
Target allocations	100.00%
Actual allocations	100.00%	100.00%
United Plan \| Equity
Defined Benefit Plan Disclosure [Line Items]
Target allocations	50.00%
Actual allocations	50.10%	51.00%
United Plan \| Fixed income
Defined Benefit Plan Disclosure [Line Items]
Target allocations	50.00%
Actual allocations	47.90%	31.00%
United Plan \| Cash and other
Defined Benefit Plan Disclosure [Line Items]
Target allocations	0.00%
Actual allocations	2.00%	18.00%
Maximum \| United Plan \| Equity
Defined Benefit Plan Disclosure [Line Items]
Actual allocations	60.00%
Minimum \| United Plan \| Equity
Defined Benefit Plan Disclosure [Line Items]
Actual allocations	40.00%

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)(i)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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